Ecophysiological Responses of Tropical Plants to Changing Concentrations of Carbon Dioxide

Ascending carbon dioxide (CO₂) concentrations are leading to accelerated climate change, which is influencing the entire earth. Although the major influence of climate change is registered in the Arctic and Antarctic, recent studies have confirmed the climate crisis in tropics also. The tropical areas are generally very rich in biodiversity and register wide variations in climatic variables due to specific features like lack of seasonality of temperature, very little fluctuation in the mean monthly temperature throughout the year and variable rainfall producing distinct and localized ecosystems and seasons. The species in the tropics are also highly specialized, which makes them particularly vulnerable to variation in the climatic variables. Elevated CO₂ concentrations are known to impart a number of biotic changes to tropical plants species. The chapter encapsulates the status of understanding of elevated CO₂ effects in the plant species inhabiting the tropics. Plant adjustment to elevated CO₂ concentration in terms of whole-plant, biological, molecular, cellular and hormonal responses is also elaborated. The importance of degree of genetic differentiation vs. phenotypic plasticity, and the transplant experiments as the key to address these fundamental questions of genotype–environment interactions determining its fitness to the changing climate and minimizes the chances of its extinction, is also highlighted.